Bag dispensers are ubiquitous throughout grocery stores and markets where produce and other items are displayed in bulk, and consumers select and bag their own merchandise for purchase. A common form of such dispensers utilizes rolls of bags, standardly referred to as “star-seal” bags, in which a tube of plastic is folded or gusseted to form multiple layers. The long tubes are welded laterally at uniform intervals to form individual bags. The bags are connected sequentially along perforated lines and wound onto a roll. A projection on the dispenser, hereinafter referred to as the tongue, engages a slot in the perforation line to separate a bag from the roll and hold the trailing bag in position for the next user.
A common complaint of users is that, once a bag has been removed, it is difficult to open. This is partially due to the bag material, which has a tendency to build up a static charge causing the thin layers of plastic to adhere to each other. However, it is also a deficiency of current dispenser designs that they do not provide a means for separating the plies as the bags are dispensed.
Multiple dispenser designs have been disclosed in prior art that address a variety of issues related to the utility of bag dispenser devices. Simhaee (U.S. Pat. Nos. 5,135,146, 5,261,585, 5,433,363) describes various features to enable one-handed operation and prevent free-wheeling of the roll during operation. In later designs, Simhaee (U.S. Pat. No. 5,752,666) incorporates an additional mechanism which traps the leading edge of the next bag to prevent dispensing more than one bag at a time. Morris (U.S. Pat. No. 5,556,019) introduced a design that allows for operation when bags are pulled across the top or bottom of the tongue, and also incorporates a means of providing constant tension on the bags regardless of how many remain on the roll.
Kannankeril (U.S. Pat. No. 5,573,168) discloses a dispenser with a guide slot to ensure more reliable contact between the perforation and the tongue. The invention also discloses a “brush” as a frictional element to assist in opening the bags, however, this mechanism is integrated into an interior panel and is therefore limited to use with the described dispenser design. Kannankeril's design also differs from the present invention in that the frictional element engages the top ply of the bag rather than the bottom ply as disclosed in the present invention. Applying friction to the top ply, as Kannankeril describes, requires the user to pull upward on the bag in order to achieve adequate frictional force to separate the bag plies. This design also applies friction prior to separation of the leading bag from the trailing bag. In order to separate the plies as a bag is dispensed, the frictional element must be positioned such that the friction is applied while the bags are being separated at the perforation line.
Daniels (U.S. Pat. Nos. 7,270,256 and 7,424,963) discloses a bag opening means that is also integrated into the dispenser and thus is limited to use with the described dispenser design. The bag opening means is also designed to facilitate opening of the leading bag as opposed to the trailing bag, as described in the present invention.
Other inventions specifically aimed at facilitating opening of bags as they are dispensed address this issue by modifying the design of the bag itself. Simhaee (U.S. Pat. No. 6,135,281) describes a method of manufacturing a continuous strip of bags in which one or more outer layers are separated entirely at the perforation line to facilitate easier separation of the bag from the roll. In another invention, Simhaee (U.S. Pat. No. 5,291,390) describes a bag design in which one ply does not contain a slit along the perforation line. The extra force required to detach this ply from the roll causes the plies to separate from each other. Campbell (U.S. Pat. No. 4,904,092) discloses the use of pressure sensitive adhesive on an outer surface of each bag which causes the front and back to separate when another is pulled from the roll or stack. Finally, Tan (U.S. Pat. No. 8,979,367) discloses features on the outer surface of the bags (either in a roll or in a stack) which releasably attach the rear wall of a first bag to the front wall of a second bag so that when the first bag is removed it causes the second bag to open before releasing. All of these solutions add extra cost to the individual bags, generating ongoing and unnecessary expense for the consumer.
In light of the foregoing discussion, it is an objective of the present invention to provide a means of dispensing plastic bags from a roll such that the bags are presented to the user in a partially opened state, without the need for specially modified bags.
Furthermore, it is an objective of the present invention to do so by providing an inexpensive accessory that can be easily retrofitted to a variety of existing plastic bag roll dispensers without the need for special tools or other apparatus.